Manufacturing

Interim, In Situ Additive Manufacturing InspectionImage-based method for real-time property inspection of printed parts

Researchers at NASA Marshall Space Flight Center have developed

a novel method for interim, in situ dimensional inspection of additively

manufactured parts. Additive manufacturing processes currently have

limited monitoring capabilities, offering users little to no options in

mitigating the high levels of product and process failures. This

technology uses both infrared (IR) and visual cameras that allow

users to monitor the build in real-time and correct the process as

needed to reduce the time and material wasted in parts that will not

meet quality specifications. The technology is especially useful for

the in-process inspection of a parts internal features (e.g., fluid

channels and passages), which cannot be easily inspected once the

print is complete. The technology has the potential to enable the

implementation of a closed-loop feedback system, allowing systems

for automatic real-time corrections.

BENEFITSRobust: leverages processing techniques to reduce false positive readings

Flexible: can be implemented in existing systems

Cost-saving: reduces time, energy, and material wasted in nonconforming parts

Accurate: uses both IR and visual cameras for thermal and spatial accuracy

APPLICATIONSAerospace: complex injectors, internal coolant passage components, heat exchangers

Automotive: exhaust system components

Medical: orthopedic implants

tech

nolo

gyso

lutio

n

Interim, In Situ Additive Manufacturing Inspection

National Aeronautics andSpace Administration

NASA Technology Transfer ProgramBringing NASA Technology Down to Earth

THE TECHNOLOGYThe in situ inspection technology for additive manufacturing combines different types of cameras strategically placed around the part to monitor its properties during construction. The IR cameras collect accurate temperature data to validate thermal math models, while the visual cameras obtain highly detailed data at the exact location of the laser to build accurate, as-built geometric models. Furthermore, certain adopted techniques (e.g., single to grouped pixels comparison to avoid bad/biased pixels) reduce false positive readings.

NASA has developed and tested prototypes in both laser-sintered plastic and metal processes. The technology detected errors due to stray powder sparking and material layer lifts. Furthermore, the technology has the potential to detect anomalies in the property profile that are caused by errors due to stress, power density issues, incomplete melting, voids, incomplete fill, and layer lift-up. Three-dimensional models of the printed parts were reconstructed using only the collected data, which demonstrates the success and potential of the technology to provide a deeper understanding of the laser-metal interactions. By monitoring the print, layer by layer, in real-time, users can pause the process and make corrections to the build as needed, reducing material, energy, and time wasted in nonconforming parts.

The NASA technology can be used to determine geometric differences (flaws) between the designed model and the printed part/component.

Interim inspection improves the quality of parts with intricate internal features like these fuel channels.

National Aeronautics and Space Administration

Agency Licensing Concierge

Marshall Space Flight Center

Huntsville, AL 35812202-358-7432Agency-Patent-Licensing@mail.nasa.gov

http://technology.nasa.gov/

www.nasa.govNP-2017-01-2351-HQ

NASA's Technology Transfer Programpursues the widest possible applicationsof agency technology to benefit UScitizens. Through partnerships andlicensing agreements with industry, theprogram ensures that NASA's investmentsin pioneering research find secondaryuses that benefit the economy, createjobs, and improve quality of life.

MFS-33013-2

MFS-TOPS-70